diff options
Diffstat (limited to 'ptrlist.c')
| -rw-r--r-- | ptrlist.c | 12 |
1 files changed, 12 insertions, 0 deletions
@@ -7,6 +7,18 @@ /// // Pointer list manipulation // ------------------------- +// +// The data structure handled here is designed to hold pointers +// but two special cases need to be avoided or need special care: +// * NULL is used by {PREPARE,NEXT}_PTR_LIST() to indicate the end-of-list. +// Thus, NULL can't be stored in lists using this API but is fine to +// use with FOR_EACH_PTR() and its variants. +// * VOID is used to replace a removed pseudo 'usage'. Since phi-nodes +// (OP_PHI) use a list to store their operands, a VOID in a phi-node +// list must be ignored since it represents a removed operand. As +// consequence, VOIDs must never be used as phi-node operand. +// This is fine since phi-nodes make no sense with void values +// but VOID is also used for invalid types and in case of errors. #include <stdlib.h> #include <string.h> |